arabica/include/SAX/helpers/XMLBaseSupport.hpp
2007-09-28 08:30:16 +00:00

126 lines
3.1 KiB
C++

#ifndef ARABICA_XMLBASE_SUPPORT_H
#define ARABICA_XMLBASE_SUPPORT_H
/*
* $Id$
*
* XMLBaseSupport is a helper class for tracking xml:base attributes.
* Usage:
* set location of the containing document by calling setDocumentLocation
* this is usually done when during the setDocumentLocator SAX event
* forward each startElement and endElement event
* to resolve a relative URL against the current base, call makeAbsolute
*
* Derived from org.apache.cocoon.xml.XMLBaseSupport.
*
* XML Base is described at http://www.w3.org/TR/xmlbase/
*/
#include <stack>
#include <utility>
#include <sstream>
#include <text/UnicodeCharacters.hpp>
#include <io/uri.hpp>
namespace Arabica
{
namespace SAX
{
template<class string_type, class string_adaptor>
struct XMLBaseConstants
{
const string_type xml;
const string_type xml_uri;
const string_type colon;
const string_type base;
XMLBaseConstants() :
xml(string_adaptor::construct_from_utf8("xml")),
xml_uri(string_adaptor::construct_from_utf8("http://www.w3.org/XML/1998/namespace")),
colon(string_adaptor::construct_from_utf8(":")),
base(string_adaptor::construct_from_utf8("base"))
{
} // XMLBaseConstants
}; // struct XMLBaseConstants
template<class string_type, class string_adaptor = Arabica::default_string_adaptor<string_type> >
class XMLBaseSupport
{
public:
typedef typename string_adaptor::value_type valueT;
typedef Attributes<string_type, string_adaptor> AttributesT;
XMLBaseSupport() :
depth_(0) { }
void setDocumentLocation(const string_type& loc)
{
bases_.push(std::make_pair(-1, loc));
} // setDocumentLocation
void startElement(const AttributesT& atts)
{
++depth_;
string_type base = atts.getValue(xbc_.xml_uri, xbc_.base);
if(base.empty())
return;
string_type baseURI = absolutise(currentBase(), base);
bases_.push(std::make_pair(depth_, baseURI));
} // startElement
void endElement()
{
if(currentDepth() == depth_)
bases_.pop();
--depth_;
} // endElement
string_type currentBase() const
{
if(!bases_.size())
return string_type();
return bases_.top().second;
} // currentBase()
string_type makeAbsolute(const string_type& spec) const
{
return absolutise(currentBase(), spec);
} // makeAbsolute
private:
string_type absolutise(const string_type& baseURI, const string_type& location) const
{
Arabica::io::URI base(string_adaptor::asStdString(baseURI));
Arabica::io::URI absolute(base, string_adaptor::asStdString(location));
return string_adaptor::construct_from_utf8(absolute.as_string().c_str());
} // absolutise
int currentDepth() const
{
if(!bases_.size())
return -1;
return bases_.top().first;
} // currentDepths
private:
typedef std::pair<int, string_type> baseInfoT;
typedef std::stack<baseInfoT> baseStackT;
baseStackT bases_;
int depth_;
const XMLBaseConstants<string_type, string_adaptor> xbc_;
// no impl
XMLBaseSupport(const XMLBaseSupport&);
XMLBaseSupport& operator=(const XMLBaseSupport&);
bool operator==(const XMLBaseSupport&);
}; // class XMLBaseSupport
} // namespace SAX
} // namespace Arabica
#endif